The present disclosure relates to a disc inspecting method of an optical information recording medium and the like, and a disc inspecting device used in the disc inspecting method.
In the related art, to confirm the shape of recording marks of a disc used to produce an optical information recording medium, developing is performed after forming the recording marks, and then it is necessary to confirm the formed recording marks by an SEM (scanning electron microscope) or the like. For this reason, the shape is not seen until the developing is performed and the observation is performed by the SEM, it takes the time for confirmation, and efficiency is not satisfactory. In the method of the related art, at the time of observation, alignment (search) between the formation position of the recording marks and the observation point of the SEM is difficult and troublesome. In addition, the observation based on the SEM is necessary, and thus it is difficult to see the shape of the entirety of the recording marks just after cutting.
Meanwhile, a method has been proposed in which a target object is irradiated with a beam of light such as laser, an optical detecting unit receives reflection light thereof, and a delicate pattern is measured (e.g., Japanese Unexamined Utility Model Registration Application No. 58-74108). In this method, the delicate pattern is measured, using a phenomenon where the irradiation light is diffused to cause disorder in the light reception of the optical detecting unit when there is a delicate line or point on the surface of the target object.